Paris, Nov 3 (IANS): John Isner rallied from a third-set deficit to edge Bulgarian Grigor Dimitrov 7-6 (12-10), 5-7, 7-6 (7-3) in the Paris Masters round-of-16 match here.

Despite firing 25 aces, the ninth-seeded Isner on Thursday struggled more than usual on serve. He faced a total of 12 break points although he managed to save all but two of them to stick around in the contest, reports Efe.

The American prevailed in an extremely tight first set, while the sixth-seeded Dimitrov got a late service break in the second set that enabled him to draw even.

The Bulgarian seemed to have the contest in hand when he took a 5-2 lead with one service break and then held a match point on Isner's serve in the eighth game.

But the American got out of that jam to hold serve, broke Dimitrov for the first time in the match in the ensuing game and then held again to level the third set at 5-5.

The match came down to a third-set tie-breaker, which Isner won comfortably to advance to Friday's quarterfinals.

Isner will square off next at this indoor hard-court ATP World Tour Masters 1000 event against Argentine Juan Martin del Potro, who defeated the Netherlands' Robin Haase.